diff --git a/mercurial/dispatch.py b/mercurial/dispatch.py
--- a/mercurial/dispatch.py
+++ b/mercurial/dispatch.py
@@ -86,30 +86,66 @@
     _initstdio()
     req = request(pycompat.sysargv[1:])
     err = None
+
+    # The logic here attempts to mimic how CPython's pythonrun.c does things.
+    # Essentially:
+    #
+    # * Exit is controlled by returning a value or raising SystemExit.
+    # * An integer value exits with that exit code.
+    # * A value of ``None`` is interpreted as ``0``.
+    # * A non-integer, non-None value results in that value being printed
+    #   and an exit code of ``1``.
+    # * SystemExit can have a ``code`` attribute containing the exit value.
     try:
-        status = (dispatch(req) or 0)
+        code = dispatch(req) or 0
     except error.StdioError as e:
         err = e
-        status = -1
+        code = -1
+    except SystemExit as err:
+        try:
+            code = err.code
+            err = None
+        except AttributeError:
+            pass
+
+    # In all cases we flush our stdio streams.
     if util.safehasattr(req.ui, 'fout'):
         try:
             req.ui.fout.flush()
         except IOError as e:
             err = e
-            status = -1
+            code = -1
+
     if util.safehasattr(req.ui, 'ferr'):
         try:
             if err is not None and err.errno != errno.EPIPE:
                 req.ui.ferr.write('abort: %s\n' %
                                   encoding.strtolocal(err.strerror))
-            req.ui.ferr.flush()
         # There's not much we can do about an I/O error here. So (possibly)
         # change the status code and move on.
         except IOError:
-            status = -1
+            code = -1
 
-    _silencestdio()
-    sys.exit(status & 255)
+    # If we got a non-integer exit code, we print that as well.
+    if not isinstance(code, int) and util.safehasattr(req.ui, 'ferr'):
+        try:
+            req.ui.ferr.write('%r\n' % code)
+        # This will ignore errors formatting the value and errors printing
+        # to stderr. That's intended. At this point, there's not much
+        # we can do about any errors.
+        except Exception:
+            pass
+
+        code = 1
+
+    if util.safehasattr(req.ui, 'ferr'):
+        try:
+            req.ui.ferr.flush()
+        except IOError:
+            # There's not much we can do about I/O errors at this point.
+            code = -1
+
+    sys.exit(code & 255)
 
 if pycompat.ispy3:
     def _initstdio():
diff --git a/tests/test-dispatch.t b/tests/test-dispatch.t
--- a/tests/test-dispatch.t
+++ b/tests/test-dispatch.t
@@ -263,12 +263,7 @@
   [42]
 
   $ hg exit returnstring 'some message'
-  Traceback (most recent call last):
-    File "*/hg", line *, in <module> (glob)
-      dispatch.run()
-    File "*/mercurial/dispatch.py", line *, in run (glob)
-      sys.exit(status & 255)
-  TypeError: unsupported operand type(s) for &: 'str' and 'int'
+  'some message'
   [1]
 
   $ hg exit returnnone
@@ -276,24 +271,14 @@
   $ hg exit returnempty
 
   $ hg exit returndict
-  Traceback (most recent call last):
-    File "*/hg", line *, in <module> (glob)
-      dispatch.run()
-    File "*/mercurial/dispatch.py", line *, in run (glob)
-      sys.exit(status & 255)
-  TypeError: unsupported operand type(s) for &: 'dict' and 'int'
+  {'key1': 'value1'}
   [1]
 
   $ hg exit systemexitint 42
   [42]
 
   $ hg exit systemexitstring 'failure message'
-  Traceback (most recent call last):
-    File "*/hg", line *, in <module> (glob)
-      dispatch.run()
-    File "*/mercurial/dispatch.py", line *, in run (glob)
-      sys.exit(status & 255)
-  TypeError: unsupported operand type(s) for &: 'str' and 'int'
+  'failure message'
   [1]
 
   $ hg exit systemexitnoarg
@@ -301,10 +286,5 @@
   $ hg exit systemexitnone
 
   $ hg exit systemexitdict
-  Traceback (most recent call last):
-    File "*/hg", line *, in <module> (glob)
-      dispatch.run()
-    File "*/mercurial/dispatch.py", line *, in run (glob)
-      sys.exit(status & 255)
-  TypeError: unsupported operand type(s) for &: 'dict' and 'int'
+  {'key1': 'value1'}
   [1]